“Crossing mainland Portugal from north to south in just over five minutes”. This is how one can grasp the speed reached in the first hypersonic test carried out under real conditions by the Institute for Plasmas and Nuclear Fusion (IPFN) at the European Shock Tube for High Enthalpy Research (ESTHER) infrastructure, located at Técnico’s Loures Campus. The test, completed on 19 November 2025, generated a hypersonic flow in the facility at around 8 km/s (Mach 25), marking Portugal’s entry into the experimental study of these phenomena. This is such a high speed that the intensity of the shock is sufficient to raise the flow temperature to values higher than those on the Sun’s surface, leading to a bright flash similar to the shooting stars occasionally visible in the sky.

“The test represents the culmination of 15 years of project development, which began in 2010 within the framework of an international consortium led by IPFN”, explains Luís Lemos Alves, head of the N-PRiME group that hosts ESTHER. “The European Space Agency (ESA) awarded this consortium the contract to build an infrastructure to support future planetary exploration missions”. For Mário Lino da Silva, a professor at Técnico and PI of the project at N-PRiME/IPFN, this result constitutes “a direct contribution to Europe’s technological independence in the aerospace field”. Hypersonic flow corresponds to speeds above Mach 5, a regime where gases reach extreme temperatures and pressures, essential for studying phenomena associated with the atmospheric re-entry of space vehicles and the exploration of planetary atmospheres such as those of Mars, Venus, Titan or Jupiter.

“The success of this first test shows that Portugal and Europe now have a unique scientific tool to study phenomena that only occur when travelling several times faster than the speed of sound”, the researcher underlines. “The ability to generate and measure hypersonic flows places us within a very restricted group of countries with technological expertise in this field”, he adds.

Operation of the ESTHER shock tube involves demanding physical conditions, namely the use of mixtures of hydrogen, oxygen and helium at very high pressures. “The main risk is that of an uncontrolled explosion in a 50-litre combustion chamber at pressures of up to 100 atmospheres”, explains Mário Lino da Silva, adding that the laboratory was designed to minimise these risks, with a reinforced structure, partially buried, and fully remote-controlled.

One of the main challenges of the project was the “validation of a prototype installation that implements several technological solutions unique in the world”. Since 2019, after the infrastructure was assembled, the different subsystems have been individually tested and validated, including the combustion chamber, the laser ignition system, the high-vacuum system, and the remote control and data acquisition systems.

The next steps involve progressively exploring the facility’s operational regime, reaching higher speeds and validating the technologies developed in an integrated manner. “This is a multidisciplinary operation that is only possible in institutions such as Técnico and IPFN, where specialists from different fields collaborate in an integrated way”, says Mário Lino da Silva. In the medium term, ESTHER is expected to directly support ESA mission planning and contribute to the development of national expertise in the hypersonic field through partnerships with academic institutions and Portuguese companies. The entry into operation of ESTHER, 76 years after the first hypersonic flight and on the 50th anniversary of ESA’s foundation, equips Europe with a facility that will enable (among other things) the fulfilment of European ambitions in accessing and exploring Space over the next 50 years.

In addition to ESTHER, the IPFN Hypersonic Plasma Laboratory has participated in all ESA planetary exploration missions to date, including Cassini-Huygens and ExoMars. With the infrastructure now operational, tests are planned on materials subjected to hypervelocity flows.

“This successful test is a source of great pride for IPFN and Técnico”, says Bruno Gonçalves, president of the research unit. “We honour the legacy of the navigators who brought new worlds to the world, now contributing to opening new paths of space exploration and helping to write this new chapter in the history of Humanity”.

In the Media:

• “Atravessar Portugal continental em pouco mais de cinco minutos é semelhante a teste hipersónico” (Observador)
• “Atravessar Portugal continental em pouco mais de cinco minutos – teste hipersónico” (MSN)
• “Técnico fez ensaio hipersónico. É como atravessar Portugal continental em pouco mais de cinco minutos” (Diário de Notícias)
• “Inédito: IST já “consegue” atravessar Portugal em cinco minutos” (ZAP.aeiou)
• “Atravessar Portugal continental em pouco mais de cinco minutos” (RTP)
• “Instituto Superior Técnico realiza primeiro ensaio hipersónico em Portugal” (TVI) 
• “Atravessar Portugal continental em pouco mais de cinco minutos” (Notícias ao Minuto)
• “IST faz teste hipersónico para estudar reentrada de foguetões” (ECO)
• “Instituto Superior Técnico realiza primeiro ensaio hipersónico em Portugal” (CNN)
• “Ensaio hipersónico no Técnico: “Atravessar Portugal continental em pouco mais de cinco minutos” (Jornal de Notícias)
• “Atravessar Portugal continental em pouco mais de cinco minutos – teste hipersónico” (LUSA)